Effective degradation of organic pollutants by CuFe@C composite derived from bimetallic MOFs synthesized through stepwise feeding method

In this work, Cu-Fe bimetal-embedded carbonaceous CuFe@C materials were prepared by high-temperature pyrolysis of CuFe-MOFs precursors synthesized through a facile two-step feeding approach. Through adjusting the reaction time of each feeding step, CuFe-MOFs of uniform dispersed crystals with controlled sizes were obtained. The carbonized composites were then applied to activate persulfate (PMS) for Reactive Brilliant Red X-3B (RBRX-3B) degradation in water. The removal rate of RBRX-3B was up to 98% in 40min in the CuFe@C600/PMS system, indicating that the CuFe@C600 catalyst showed excellent sulphate radical-based oxidation (SR-AO) activity in the degradation process. The effects of PMS dosage, initial pH, RBRX-3B concentration on the degradation efficiency were investigated in detail. Based on quenching experiments, a possible mechanism for the CuFe@C600/PMS system was proposed. The catalyst had good reusability, in which the removal rate of RBRX-3B could attain 82% after 5 times of repeated recycling. It also showed satisfactory removal effect on other organic pollutants, i.e. Congo red, Methyl orange, Reactive blue and p-nitrophenol. This study provided a valuable strategy the treatment of wastewater containing organic pollutants using MOFs-derived materials.